Intraoperative Evaluation of Vascular Wall and Hemodynamics of the Carotid Artery by Ultrasonography in Carotid Endarterectomy

Abstract

Various kinds of intraoperative monitoring are used in carotid endarterectomy (CEA) such as somatosensory encephalogram or transcranial Doppler for detection of cerebral ischemia or microembolism. However, anatomical information about arterial wall, which is manipulated directly, is poorly monitored during operation. Postoperative ischemic complication and restenosis can be occasionally caused by failure of manipulation of intimal stump during CEA. Technical defects can be repaired if intramural problems are detected by ultrasonography (USG) during operation.
In 24 cases of CEA between October 2001 and March 2004, we performed intraoperative USG to monitor the arterial wall and hemodynamics. Intraoperative digital angiography (DSA) was performed to compare USG findings. We were able to grasp characteristics and extension of plaque before arteriotomy. It was especially useful for the cases whose plaque end was obscure by DSA. An intimal stump on both sides after CEA could be recognized by B-mode scans. Peak systolic velocities measured by the pulse Doppler method were decreased in all cases after CEA. Three cases were repaired following recognition of technical defects by USG. One was an intimal flap over 2 mm; the others were due to residual common carotid artery lesion.
In conclusion, intraoperative USG in CEA was useful in terms of grasping both information of vascular wall and intraluminal hemodynamics in real time, and allowed the detection of technical defects that required surgical repair. Intraoperative USG monitoring may improve operative results by reducing technical defects.